1. Field of the Invention
This invention relates to electronic tone synthesis and in particular is concerned with a means for generating tones from acoustic sources.
2. Description of the Prior Art
Various attempts have been made for many years to construct apparatus for imitating the human singing voice. The early theatre pipe organs had a solo stop called the Vox Humana (human voice). This stop was implemented as a rank of reed pipes which only remotely reminded one of sound of human origin.
Vocoder-type implementations have been used to produce human-like sounds. To obtain a singing quality a microphone is used to convert a real human singing tone into an electrical signal. By means of a frequency follower, the fundamental frequency of the input signal can be tracked and then transposed to musical pitches in response to the actuation of keyboard switches. The resultant sounds, while not an exact replica of the input sound, have a human-like tone quality.